Warpage resistant semiconductor package and method for manufacturing the same

ABSTRACT

A semiconductor package and a method for manufacturing the same is provided for minimizing or preventing warpage and twisting of semiconductor chip bodies as a result of thinning them during gringing. The semiconductor package includes a semiconductor chip body and a substrate. The semiconductor chip body has a first surface, a second surface facing away from the first surface, through-electrodes which pass through the semiconductor chip body and project from the second surface, and a warpage prevention part which projects in the shape of a fence along an edge of the second surface. The substrate has a substrate body and connection pads which are formed on an upper surface of the substrate body, facing the second surface, and which are connected with the projecting through-electrodes.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to Korean patent applicationnumber 10-2007-0123758 filed on Nov. 30, 2007, which is incorporatedherein by reference in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates to a semiconductor package and a methodfor manufacturing the same.

These days, technologies for semiconductor packages includingsemiconductor chips have been rapidly developed.

Since the semiconductor chip manufactured through a semiconductor chipmanufacturing process has input and output terminals of a very finesize, it is difficult to directly mount the semiconductor chip to aprinted circuit board, etc. Also, since the semiconductor chip is likelyto break even by small shocks and/or vibrations, the semiconductor chipis generally packaged through a packaging process.

A semiconductor package having undergone the packaging process has inputand output terminals, which are suitable for mounting to a printedcircuit board, and does not easily break by externally applied shocksand/or vibrations.

Recently, a technique has been disclosed in the art, in which the rearsurface of the wafer formed with a plurality of semiconductor chips isground down in an effort to decrease the thickness of the semiconductorchips and to reduce the volume of semiconductor packages.

However, as the rear surface of the wafer is ground down and thethickness of the wafer or the semiconductor chips included in the waferdecreases, and as a result the wafer or the semiconductor chips arelikely to be warped or twisted.Due to this fact, various other defectscan arise as a result of this course of manufacturing a semiconductorpackage.

SUMMARY OF THE INVENTION

Embodiments of the present invention are directed to a semiconductorpackage which has a decreased thickness and which has a propensity toprevent being warped or twisted.

Also, embodiments of the present invention are directed to a method formanufacturing the semiconductor package.

The semiconductor package comprises a semiconductor chip having asemiconductor chip body which has a first surface and a second surfacefacing away from the first surface, through-electrodes which passthrough the semiconductor chip body and project from the second surface,and a warpage prevention part which projects in the shape of a fencealong an edge of the second surface; and a substrate having a substratebody and connection pads which are formed on an upper surface of thesubstrate body, facing the second surface, and are connected with theprojecting through-electrodes.

The semiconductor chip body is located in a chip region, and the warpageprevention part is located along scribe line regions which are definedaround the chip region.

A length of the through-electrodes, which project from the secondsurface, is substantially the same as a height of the warpage preventionpart.

The warpage prevention part is intermittently formed on the secondsurface.

The through-electrodes projecting from the second surface include soldermembers.

At least two semiconductor chips are located on the substrate.

The semiconductor package may further comprises bonding pads located onthe first surface with the through-electrodes respectively passingthrough the bonding pads.

The method for manufacturing the semiconductor package comprises thesteps of preparing a semiconductor chip having a first surface, a secondsurface facing away from the first surface, and a chip regionpartitioned by scribe regions; forming through-electrodes which passthrough the first surface and the second surface; selectively etchingthe chip region on the second surface of the semiconductor chip toproject the through-electrodes and a warpage prevention part,corresponding to the scribe regions, from the etched second surface; andconnecting the through-electrodes projecting from the second surface ofthe semiconductor chip and connection pads of a substrate, correspondingto the through-electrodes, using conductive members.

The step of forming the through-electrodes comprises the steps ofdefining grooves which pass through bonding pads formed to on the firstsurface and have a depth less than a thickness of the semiconductorchip; and filling the grooves with a metal.

Between the step of defining the grooves and the step of filling thegrooves with the metal, the method may further comprise the step offorming a metal seed layer on inner surfaces of the grooves.

The step of projecting the warpage prevention part comprises the stepsof grinding the second surface and exposing the through-electrodes;covering the scribe regions on the second surface with a photoresistpattern, and exposing the chip region on the second surface; and etchingthe chip region on the second surface using the photoresist pattern asan etch mask.

After the step of etching the chip region on the second surface, thephotoresist pattern is removed from the second surface.

At least two semiconductor chips are stacked.

The semiconductor chips are individually parted from each other alongthe scribe regions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view illustrating a semiconductor package inaccordance with an embodiment of the present invention.

FIG. 2 is a perspective view illustrating the lower surface of thesemiconductor chip shown in FIG. 1.

FIG. 3 is a perspective view illustrating a semiconductor package inaccordance with another embodiment of the present invention.

FIGS. 4 through 9 are cross-sectional views illustrating a method formanufacturing a semiconductor package in accordance with a still anotherembodiment of the present invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS

FIG. 1 is a cross-sectional view illustrating a semiconductor package inaccordance with an embodiment of the present invention. FIG. 2 is aperspective view illustrating the lower surface of the semiconductorchip shown in FIG. 1.

Referring to FIGS. 1 and 2, a semiconductor package 300 includessemiconductor chips 100 and a substrate 200.

Each semiconductor chip 100 has a semiconductor chip body 110,through-electrodes 120, and a warpage prevention part 130. In addition,each semiconductor chip 110 can further have solder members 140 whichare electrically connected with the through-electrodes 120.

The semiconductor chip body 110 has a first surface 112, a secondsurface 114, a circuit part (not shown), and bonding pads 116. Thesemiconductor chip body 110 is located, for example, in a chip regionCR.

The semiconductor chip body 110 located in the chip region CR has, forexample, the shape of a rectangular hexahedron. The first surface 112 ofthe semiconductor chip body 110 faces away from the second surface 114.

The circuit part is formed in the semiconductor chip body 110. Thecircuit part can include a data storage section for storing data and adata processing section for processing data.

The bonding pads 116 are located, for example, on the first surface 112of the semiconductor chip body 110 in a plural number. The respectivebonding pads 116 are electrically connected with the circuit part.

The bonding pads 116 can be arranged in line on the center portion ofthe first surface 112 or on the edge portions of the first surface 112.In the present embodiment, the bonding pads 116 are arranged, forexample, on the center portion of the first surface 112.

The through-electrodes 120 pass through the bonding pads 116 which areformed on the first surface 112 of the semiconductor chip body 110 andportions of the semiconductor chip body 110 which correspond to thebonding pads 116. Unlike this, it can be envisaged that thethrough-electrodes 120 pass through other portions of the semiconductorchip body 110, which do not correspond to the bonding pads 116, and areconnected with the bonding pads 116 via redistribution lines (notshown).

The through-electrodes 120 have the shape of a column. Eachthrough-electrode 120 has a first end 122 which is formed on the firstsurface 112 and a second end 124 which faces away from the first end122. The second end 124 of the through-electrode 120 projects from thesecond surface 114 by a predetermined length L.

As described above, the through-electrodes 120, which pass through thebonding pads 116 and the portions of the semiconductor chip body 110,can have the shape of a column. In the present embodiment, copper can beused as the material of the through-electrodes 120.

Meanwhile, a metal seed layer (not shown) can be applied to the surfacesof the through-electrodes 120. The exemplary materials for the metalseed layer can include titanium, nickel and vanadium.

The warpage prevention part 130 is formed in scribe line regions SLRwhich are defined around the chip region CR in which the semiconductorchip body 110 is located.

For example, the warpage prevention part 130 projects in the shape of afence from the second surface 114 of the semiconductor chip body 110 inthe scribe line regions SLR.

The warpage prevention part 130, which projects in the shape of a fencefrom the second surface 114 of the semiconductor chip body 110 in thescribe line regions SLR defining a quadrangular contour, prevents orsuppresses the semiconductor chip body 110 from being warped by warpingstress which is induced to warp or twist the semiconductor chip body110.

Although it was described and illustrated in the present embodiment thatthe warpage prevention part 130 is formed in the shape of a fence in thescribe line regions SLR as shown in FIG. 2, unlike this, according tothe present invention, a plurality of warpage prevention parts 135 canbe intermittently located in the scribe line regions SLR as shown inFIG. 3.

The height of the warpage prevention part 130, which projects in theshape of a fence from the second surface 114 of the semiconductor chipbody 110, is, for example, substantially the same as the length L bywhich the through-electrodes 120 project from the second surface 114 ofthe semiconductor chip body 110.

A plurality of semiconductor chips 100 can be stacked as shown inFIG. 1. At this time, the second surface 114 of an upper semiconductorchip 100 is located over the first surface 112 of a lower semiconductorchip 100, and due to this fact, the through-electrodes 120 of the uppersemiconductor chip 100 face the bonding pads 116 of the lowersemiconductor chip 100.

The solder members 140 electrically connect the bonding pads 116 of thelower semiconductor chip 100 with the second ends 124 of thethrough-electrodes 120 of the upper semiconductor chip 100, so that theplurality of semiconductor chips 100 can be stacked and be electricallyconnected with one another.

In order to electrically connect the plurality of semiconductor chips100 with one another, the solder members 140 can be located on thebonding pads 116 of the respective semiconductor chips 100. Unlike this,the solder members 140 can be located on the second ends 124 of thethrough-electrodes 120 of the respective semiconductor chips 100.

The substrate 200 includes a substrate body 210 and connection pads 220.

The substrate body 210 has an upper surface 201 and a lower surface 203which faces away from the upper surface 201.

The connection pads 220 are located on the upper surface 201 of thesubstrate body 210. The connection pads 220 are located at positionswhich correspond to the through-electrodes 120 projecting from thesecond surface 114 of the semiconductor chip 100.

In addition, the substrate 200 can further include ball land patterns205 and solder balls 207 which are located on the lower surface 203 ofthe substrate body 210. The ball land patterns 205 are electricallyconnected with the connection pads 220 which are located on the uppersurface 201 of the substrate body 210, and the solder balls 207 areelectrically connected to the ball land patterns 205.

FIGS. 4 through 9 are cross-sectional views illustrating a method formanufacturing a semiconductor package in accordance with a still anotherembodiment of the present invention.

Referring to FIG. 4, in order to manufacture a semiconductor package,for example, a semiconductor chip 100 is first manufactured.

For example, a plurality of semiconductor chips 100 are formed on awafer 160 in the type of a matrix through a semiconductor chipmanufacturing process. Scribe lines SL are formed between semiconductorchips 100 such that the semiconductor chips 100 can be parted from thewafer 160 along the scribe lines SL.

Regions of the wafer 160, in which the semiconductor chips 100 areformed, are defined as chip regions CR, and regions of the wafer 160, inwhich the scribe lines SL for partitioning the chip regions CR areformed, are defined as scribe line regions SLR.

Each of the plurality of semiconductor chips 100 formed on the wafer 160includes a semiconductor chip body 110. The semiconductor chip body 110has a first surface 112 and a second surface 114 which faces away fromthe first surface 112.

Bonding pads 116, which are electrically connected with the circuit part(not shown) formed in the semiconductor chip body 110, are located onthe first surface 112. For example, the bonding pads 116 can be arrangedin line on the center portion of the first surface 112 of thesemiconductor chip body 110 or on the edge portions of the first surface112 of the semiconductor chip body 110. In the present embodiment, thebonding pads 116 are arranged, for example, on the center portion of thefirst surface 112 of the semiconductor chip body 110.

Referring to FIGS. 5 and 6, after the semiconductor chips 100 aremanufactured, through-electrodes 120 are formed in each semiconductorchip body 110 in such a way as to pass through the first and secondsurfaces 112 and 114 of the semiconductor chip body 110.

Referring to FIG. 5, after the semiconductor chips 100 are manufactured,for example, grooves 121 to be used for forming through-electrodes aredefined through the bonding pads 116 formed on the first surface 112 ofeach semiconductor chip 100 and in portions of the semiconductor chip100 which correspond to the bonding pads 116. In the present embodiment,the depth of the grooves 121 is set to be less than the thickness of thesemiconductor chip 100.

After the grooves 121 to be used for forming through-electrodes aredefined in the semiconductor chip 100, a metal seed layer is formed onthe inner surfaces of the grooves 121 to allow through-electrodes to beformed in the grooves 121 through a plating process.

The metal seed layer is a metal layer which has a small thickness. Theexemplary metals, which can be used for forming the metal seed layer,can include titanium, nickel and vanadium.

After the metal seed layer is formed, the through-electrodes 120 havingthe shape of a column are formed in the grooves 121 through a platingprocess. Copper can be used for forming the through-electrodes 120.

After the through-electrodes 120 are formed, solder members 140 such assolder balls can be formed on the bonding pads 116 which are formed onthe first surface 112 of the semiconductor chip body 110.

Referring to FIG. 6, after the through-electrodes 120 are formed, inorder to reduce the volume of a semiconductor package, the secondsurface 114 of the semiconductor chip body 110 is grinded through agrinding process, such that the thickness of the semiconductor chip body110 measured between the first surface 112 and the second surface 114decreases from T1 to T2.

In FIG. 6, as the second surface 114 of each semiconductor chip body 110is grinded through the grinding process, warpage or twisting can occurin the wafer 160 having the semiconductor chips 100. The warpage andtwisting of the wafer 160 occurs in proportion to the thickness of thesemiconductor chip body 110 to be grinded.

Referring to FIG. 7, in order to minimize, suppress or prevent thewarpage and twisting of the semiconductor chip body 110 even with thegrinding of the second surface 114 of the semiconductor chip body 110, aphotoresist film (not shown) is to formed on the entire area of thesecond surface 114 of the grinded semiconductor chip body 110. Thephotoresist film can be formed, for example, through a spin coatingprocess.

The photoresist film applied to the second surface 114 of the grindedsemiconductor chip body 110 is patterned through a photo processincluding a lithography process and a development process, and throughthis, a photoresist pattern 170 is formed on the second surface 114 ofthe semiconductor chip body 110 in correspondence with the scribe lineregions SLR.

Referring to FIG. 8, after the photoresist pattern 170 is formed on thesecond surface 114 of the semiconductor chip body 110, the secondsurface 114 of the semiconductor chip body 110 is etched using thephotoresist pattern 170 as an etch mask, and thereby, a warpageprevention part 130, which projects from the second surface 114, isformed on the second surface 114 of the semiconductor chip body 110along the scribe line regions SLR.

After the warpage prevention part 130 is formed on the second surface114 of each semiconductor chip body 110, the photoresist pattern 170 isremoved from the second surface 114 through an ashing process or astripping process.

The warpage prevention part 130 is formed along the scribe line regionsSLR, and as a result of this, when viewing the wafer 160 from the top,warpage prevention parts 130 define the shape of a lattice. Due to thepresence of the warpage prevention parts 130, the warpage of the wafer160 and the semiconductor chips 100 formed on the wafer 160 isprevented.

As the scribe line regions SLR are cut by a sawing machine, theplurality of semiconductor chips 100, which are formed on the wafer 160,are individually parted. Although the parted semiconductor chips 100have a small thickness, they have the warpage prevention parts 130.Therefore, even though the plurality of semiconductor chips 100 areparted from the wafer 160, the warpage and twisting of the semiconductorchips 100 is minimized, suppressed or prevented due to the presence ofthe warpage prevention parts 130.

Referring to FIG. 9, at least two of the semiconductor chips 100 partedfrom the wafer 160 are stacked, and the stacked semiconductor chips 100are electrically connected with each other by the solder members 140.

At least two stacked semiconductor chips 100 are located on thesubstrate body 210 of the substrate 200 having the connection pads 220on which solder members are formed, and the through-electrodes 120 ofthe semiconductor chip 100 are electrically connected with the soldermembers formed on the connection pads 220, whereby the manufacture of asemiconductor package 300 as shown in FIG. 9 is completed.

As is apparent from the above description, in the present invention,after a plurality of semiconductor chips are formed on a wafer, the rearsurface of the wafer is grinded to reduce the volume of thesemiconductor chips, and warpage prevention parts are formed on the rearsurface of the grinded wafer, whereby it is possible to minimize,suppress or prevent the wafer or the semiconductor chips formed on thewafer from being warped and twisted.

Although specific embodiments of the present invention have beendescribed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and the spirit of theinvention as disclosed in the accompanying claims.

1. A method for manufacturing a semiconductor package, comprising thesteps of: preparing a semiconductor chip having a first surface, asecond surface facing away from the first surface, and a chip regionpartitioned by scribe regions; forming through-electrodes which passthrough the first surface and the second surface; selectively etchingthe chip region on the second surface of the semiconductor chip and toproject the through-electrodes and a warpage prevention part,corresponding to the scribe regions, from the etched second surface; andconnecting the through-electrodes, projecting from the second surface ofthe semiconductor chip, with the connection pads of a substrate,corresponding to the through-electrodes, using conductive members. 2.The method according to claim 1, wherein the step of forming thethrough-electrodes comprises the steps of: defining grooves which passthrough bonding pads formed on the first surface and have a depth lessthan a thickness of the semiconductor chip; and filling the grooves witha metal.
 3. The method according to claim 2, wherein, between the stepof defining the grooves and the step of filling the grooves with themetal, the method further comprises the step of forming a metal seedlayer on inner surfaces of the grooves.
 4. The method according to claim2, wherein the step of etching the chip region to project the warpageprevention part comprises the steps of: grinding the second surface andexposing the through-electrodes; covering the scribe regions on thesecond surface using a photoresist pattern, and exposing the chip regionon the second surface; and etching the chip region on the second surfaceusing the photoresist pattern as an etch mask.
 5. The method accordingto claim 4, wherein, after the step of etching the chip region on thesecond surface, the photoresist pattern is removed from the secondsurface.
 6. The method according to claim 1, wherein at least twosemiconductor chips are stacked.
 7. The method according to claim 6,wherein the semiconductor chips are individually parted from each otheralong the scribe regions.